小题1:

The woman doctor d__________________ all her life to medical work for Chinese women and children in those years

小题2:

It is w__________________ to spend the whole day in the forest，because you can know more about the animals’ world. 

小题3:

It is quite c_________________ that he will be successful in the final match.

小题4:

In no time，the exciting news spread t____________________ the whole country.

小题5:

He was determined to o___________________ the difficulties he met in his study.

小题6:

After class the students can take part in v________________ activities ,such as playing basketball, surfing the Internet and so on.

小题7:

The farmers in this area had a good harvest last year thanks to the s_______________farming.

小题8:

I’m totally c__________________. Could you explain that again?

窦房结P细胞动作电位0期去极的离子基础是

A．Ca2+内流

B．Na+内流

C．K+内流

D．Ca2+外流

E．K+外流